Data entry control panels have long been known and typically employ a plurality of switches with an indicator to allow the entry of data or commands and the display of varying status of associated parameters.
Some data entry control panels employ dome switches such as the following listed patents owned by the assignee of the present invention and incorporated by reference herein:
U.S. Pat. No. 3,967,084 issued to Walter R. Pounds on Jun. 29, 1976 describing KEYBOARD SWITCH ASSEMBLIES HAVING TWO FOOT SUPPORT LEGS ON DOME-SHAPED CONTACT MEMBER.
U.S. Pat. No. 4,042,439 issued to Walter R. Pounds on Aug. 16, 1977 describing a METHOD OF MAKING KEYBOARD ASSEMBLIES.
U.S. Pat. No. 4,085,306 issued to Bill D. Dunlap on Apr. 18, 1978 describing KEYBOARD SWITCH ASSEMBLIES.
U.S. Pat. No. 4,195,210 issued to Walter R. Pounds et al on Mar. 25, 1980 describing SWITCHING ASSEMBLIES.
U.S. Pat. No. 4,352,968 issued to Walter R. Pounds on Oct. 5, 1982 describing an ELASTOMERIC BOOT FOR A KEYBOARD SUBASSEMBLY.
Back lighted control panels are also old. When a control panel is back lighted it is difficult to achieve adequate illumination over the entire surface of the panel, while avoiding undesirable glare in portions of the panel. Some skilled in the art were of the opinion that a functioning control panel could not be built having a thin section less than about one-half inch.